AUSTIN, TX — Researchers at the University of Texas have done their part to answer one of life’s big questions: Why do humans have sex? According two studies involving nearly 2,000 people, there are at least 237 reasons. The results were published in the August issue of the scholarly journal Archives of Sexual Behavior.Psychological researchers Cindy M. Meston and David M. Buss believe their research is the first thorough taxonomy of sexual motivation.

As might be expected, the reasons ranged from the sublime (“I wanted to feel closer to God”) to the ridiculous (“I was bored”) and from the altruistic (“I wanted my partner to feel good about himself/herself”) to the predatory (“I wanted to get a promotion”).

Some respondents said they had sex to feel powerful, others to debase themselves. Some wanted to impress their friends, others to harm their enemies (i.e., “I wanted to break up a rival’s relationship”).

The good news is that the most popular reason among both men and women was “I was attracted to the other person.” Also among the top 10 reasons on both male and female lists was the exquisitely simple “It’s fun.”

In the first study Buss and Meston conducted, more than 400 men and women were asked to identify reasons people have sex. In the second, the researchers asked more than 1,500 undergraduate students about their experiences and attitudes.

The identified four major factors and 13 sub-factors for why people have sex:
• Physical reasons such as to reduce stress (“It seemed like good exercise”), feel pleasure (“It’s exciting”), improve or expand experiences (“I was curious about sex”) and engage physical desirability (“The person was a good dancer”).
• Goal-based reasons, including utilitarian or practical considerations (“I wanted to have a baby”), social status (“I wanted to be popular”) and revenge (“I wanted to give someone else a sexually transmitted disease”).
• Emotional reasons such as love and commitment (“I wanted to feel connected”) and expression (“I wanted to say ‘thank you’”).
• Insecurity-based reasons, including self-esteem (“I wanted the attention”), a feeling of duty or pressure (“My partner kept insisting”) and to guard a mate (“I wanted to keep my partner from straying”).

“Why people have sex is extremely important but rarely studied,” Buss, a professor of psychology at UT and the author of The Evolution of Desire, said. “Surprisingly, many scientists assume the answer is obvious, but people have different reasons for having sex, some of which are rather complex.”

Some also are rather obscure. Take No. 173 on the list for example: “I wanted to get rid of a headache.” Who knew that argument worked on both sides of the sheets? Even more abstruse: “I wanted to change the topic of conversation.” (Yes, sex will do that, all right.) More understandable were responses like “Sex helps me fall asleep,” “I wanted to make my partner feel powerful” or “I wanted to keep warm.”

Lame reasons also were represented: “Someone dared me.”

Buss has studied mating strategies and rituals worldwide, but he admitted some of the more Machiavellian responses surprised even him.

“I was truly astonished by this richness of sexual psychology,” he told the New York Times.

Truly astonishing for the masses, however, may be the myth-busting in which the list engages. Although female subjects were more likely than males to cite emotional reasons like “I wanted to express my love for the person” and “I realized I was in love,” they were far less likely than men to admit using sex as a tool to gain status (promotions and contacts with celebrities, for example) or resources (raises or favors) — and that runs counter to conventional wisdom.

“Although I knew that having sex has consequences for reputation, it surprised me that people, notably men, would be motivated to have sex solely for social status and reputation enhancement,” Buss told the Times.

Thoroughly in keeping with what many consider to be a “typical” male mindset, men also were more likely than women to admit having sex for reasons like “I was slumming” or “the opportunity presented itself.”

The list also is notable for what it doesn’t contain. For example, Joan Crawford’s famous “I need sex for a clear complexion” was nowhere to be found, nor was anything about “having fun before I get too old.”